Security systems are often installed within and around buildings such as commercial, residential, or governmental buildings. Examples of these buildings include offices, hospitals, warehouses, schools or universities, shopping malls, government offices, and casinos. The security systems typically include components such as system controllers, access control readers, video surveillance cameras, network video recorders (NVRs), and door controllers, to list a few examples.
The access control readers are often installed at access points of the buildings to control access to restricted areas, such as buildings or areas of the buildings. Examples of access points include front and interior doors of a building, elevators, hallways connecting two areas of a building, to list a few examples. The access control readers authenticate identities of (or authorize) individuals and then permit those authenticated individuals to access the restricted areas through the access points. Typically, individuals interact with the access control readers by swiping keycards or bringing contactless smart cards within range (approximately 2-3 inches or 5 centimeters) of a reader. The access control readers read the information of the keycards and then the access control systems determine if the individuals are authorized to access the restricted areas. If the individuals are authorized to enter the restricted areas, then the access control readers allow access to the restricted areas by unlocking locked doors, signaling that doors should be unlocked, activating elevators, or generating alarms upon unauthorized entry, for example.
More recently, frictionless access control and tracking systems have been proposed. These systems use wireless technology that enables a more transparent method for identifying and tracking individuals while providing similar access control as traditional systems and methods. The systems can automatically identify individuals as they approach or stand in threshold areas of the access points. Threshold areas are typically areas within close proximity to the access points, such as entrances of the restricted areas and/or areas in front of doors, in examples. These systems accomplish these tasks without requiring the individuals to swipe or wave keycards, for example, at card readers, and can more continuously track those users in and around buildings.
In these systems, users carry active wireless devices on their person. These user devices transmit user information, such as credentials, that identify the users to a wireless receiving device, or positioning unit. In some cases, the user devices are mobile computing devices such as smart phones or tablet computing devices. In other cases, dedicated fobs are used.
In one implementation, the positioning units are installed above access points. The positioning units include directional antennas for detecting if a user with a user device is in close proximity to the access point. The positioning units might also include an omni directional antenna for communicating with user devices in the broader vicinity to the access point. When user information is received by the positioning units, the positioning units can then determine locations of the user devices (and thus the locations of the users) comparing the strength of the signals received by the directional antenna against the signal strength received by the omni directional antenna.